Infectious diseases caused by bacterial pathogens are widespread, presenting major challenges to our healthcare systems, from treatment needs to preventions in hospital settings and food and water supplies, and to the global public health in general. Especially, the rise in multidrug resistance among bacterial pathogens has threatened the effective prevention and treatment of bacterial infections. As new resistance mechanisms emerge and spread globally as fast as new drug development, the realm of traditional antibiotics/antimicrobial agents is no longer able to meet society's expectations. This has motivated a global search for alternative antimicrobial strategies. Some of the newly discovered materials and their associated technologies, particularly those may be applied in various stages prior to outbreaks of infection, have shown great potential. Among the most effective are photo-activated antimicrobial agents, especially those responsive to visible light, providing solutions i prevention of bacterial infections across a wide variety of applications. Carbon dots are generally small carbon nanoparticles with surface passivation. They are known for their broad optical absorption over the entire visible spectrum, and share similar mechanisms with those of typical photosensitizers, which under photo irradiation generate reactive oxygen species (ROS), but extend the photo- activation to visible light, especially for the opportunity to potentially us natural sunlight. Their visible-light photodynamic effect has been demonstrated for the killing of cancer cells. As such the photo toxicity against bacteria in this and other mechanisms is anticipated. Further, the photo toxicity should be mechanistically tunable with dot surface modification and/or doping with other elements for carbon-based hybrid dots. The project aims 1) To Exploit the Visible-Light-Activated Antibacterial Functions of Carbon Dots; and 2) To Develop Carbon-Based Hybrid Nano-Dots for Enhanced Antibacterial Performance. Development of such photochemical antimicrobial technology will address some major challenges in infectious disease prevention and treatment. The research topic and environment will provide excellent opportunities to undergraduate and graduate students, especially those from underrepresented groups, for their contributions to the performance and success of the project and, at the same time, valuable trainings in the interdisciplinary area.